Glutamate receptors (GLRs) are ligand-gated membrane bound proteins which are prevalent in animal nervous systems where they reside on the post-synaptic membrane. This project will examine the role of glutamate receptor gene homologues in plants which have recently been discovered in Arabidopsis. To do this, I will use a reverse and forward genetic approach to study the role of these genes in Arabidopsis growth and development. With a reverse genetic approach,, transgenic Arabidopsis plants will be created with low or no expression of GLRs using both an antisense and gene knockout approach. By using forward genetics, I will screen for mutants insensitive to BMAA, a neuroactive plant derived agonist of GLRs that appears to inhibit photo morphogenesis in Arabidopsis. BMAA insensitive mutants (bim) may be disrupted in GLR genes or other genes involved in a GLR response cascade. Plants derived from both the forward and reverse genetic approach will be tested for alterations in light responses at the morphological and molecular level. Finally, the spatial and temporal expression patterns of Arabidopsis GLRs that are found to be important for normal plant function and development from these studies will be examined. This combined approach will help in deciphering the role of these genes in Arabidopsis and perhaps also in animals.